xref: /openbmc/qemu/hw/pci-host/articia.c (revision 542b10bd)
1 /*
2  * Mai Logic Articia S emulation
3  *
4  * Copyright (c) 2023 BALATON Zoltan
5  *
6  * This work is licensed under the GNU GPL license version 2 or later.
7  *
8  */
9 
10 #include "qemu/osdep.h"
11 #include "qemu/log.h"
12 #include "qapi/error.h"
13 #include "hw/pci/pci_device.h"
14 #include "hw/pci/pci_host.h"
15 #include "hw/irq.h"
16 #include "hw/i2c/bitbang_i2c.h"
17 #include "hw/intc/i8259.h"
18 #include "hw/pci-host/articia.h"
19 
20 /*
21  * This is a minimal emulation of this chip as used in AmigaOne board.
22  * Most features are missing but those are not needed by firmware and guests.
23  */
24 
25 OBJECT_DECLARE_SIMPLE_TYPE(ArticiaState, ARTICIA)
26 
27 OBJECT_DECLARE_SIMPLE_TYPE(ArticiaHostState, ARTICIA_PCI_HOST)
28 struct ArticiaHostState {
29     PCIDevice parent_obj;
30 
31     ArticiaState *as;
32 };
33 
34 /* TYPE_ARTICIA */
35 
36 struct ArticiaState {
37     PCIHostState parent_obj;
38 
39     qemu_irq irq[PCI_NUM_PINS];
40     MemoryRegion io;
41     MemoryRegion mem;
42     MemoryRegion reg;
43 
44     bitbang_i2c_interface smbus;
45     uint32_t gpio; /* bits 0-7 in, 8-15 out, 16-23 direction (0 in, 1 out) */
46     hwaddr gpio_base;
47     MemoryRegion gpio_reg;
48 };
49 
50 static uint64_t articia_gpio_read(void *opaque, hwaddr addr, unsigned int size)
51 {
52     ArticiaState *s = opaque;
53 
54     return (s->gpio >> (addr * 8)) & 0xff;
55 }
56 
57 static void articia_gpio_write(void *opaque, hwaddr addr, uint64_t val,
58                                unsigned int size)
59 {
60     ArticiaState *s = opaque;
61     uint32_t sh = addr * 8;
62 
63     if (addr == 0) {
64         /* in bits read only? */
65         return;
66     }
67 
68     if ((s->gpio & (0xff << sh)) != (val & 0xff) << sh) {
69         s->gpio &= ~(0xff << sh | 0xff);
70         s->gpio |= (val & 0xff) << sh;
71         s->gpio |= bitbang_i2c_set(&s->smbus, BITBANG_I2C_SDA,
72                                    s->gpio & BIT(16) ?
73                                    !!(s->gpio & BIT(8)) : 1);
74         if ((s->gpio & BIT(17))) {
75             s->gpio &= ~BIT(0);
76             s->gpio |= bitbang_i2c_set(&s->smbus, BITBANG_I2C_SCL,
77                                        !!(s->gpio & BIT(9)));
78         }
79     }
80 }
81 
82 static const MemoryRegionOps articia_gpio_ops = {
83     .read = articia_gpio_read,
84     .write = articia_gpio_write,
85     .valid.min_access_size = 1,
86     .valid.max_access_size = 1,
87     .endianness = DEVICE_LITTLE_ENDIAN,
88 };
89 
90 static uint64_t articia_reg_read(void *opaque, hwaddr addr, unsigned int size)
91 {
92     ArticiaState *s = opaque;
93     uint64_t ret = UINT_MAX;
94 
95     switch (addr) {
96     case 0xc00cf8:
97         ret = pci_host_conf_le_ops.read(PCI_HOST_BRIDGE(s), 0, size);
98         break;
99     case 0xe00cfc ... 0xe00cff:
100         ret = pci_host_data_le_ops.read(PCI_HOST_BRIDGE(s), addr - 0xe00cfc, size);
101         break;
102     case 0xf00000:
103         ret = pic_read_irq(isa_pic);
104         break;
105     default:
106         qemu_log_mask(LOG_UNIMP, "%s: Unimplemented register read 0x%"
107                       HWADDR_PRIx " %d\n", __func__, addr, size);
108         break;
109     }
110     return ret;
111 }
112 
113 static void articia_reg_write(void *opaque, hwaddr addr, uint64_t val,
114                               unsigned int size)
115 {
116     ArticiaState *s = opaque;
117 
118     switch (addr) {
119     case 0xc00cf8:
120         pci_host_conf_le_ops.write(PCI_HOST_BRIDGE(s), 0, val, size);
121         break;
122     case 0xe00cfc ... 0xe00cff:
123         pci_host_data_le_ops.write(PCI_HOST_BRIDGE(s), addr, val, size);
124         break;
125     default:
126         qemu_log_mask(LOG_UNIMP, "%s: Unimplemented register write 0x%"
127                       HWADDR_PRIx " %d <- %"PRIx64"\n", __func__, addr, size, val);
128         break;
129     }
130 }
131 
132 static const MemoryRegionOps articia_reg_ops = {
133     .read = articia_reg_read,
134     .write = articia_reg_write,
135     .valid.min_access_size = 1,
136     .valid.max_access_size = 4,
137     .endianness = DEVICE_LITTLE_ENDIAN,
138 };
139 
140 static void articia_pcihost_set_irq(void *opaque, int n, int level)
141 {
142     ArticiaState *s = opaque;
143     qemu_set_irq(s->irq[n], level);
144 }
145 
146 /*
147  * AmigaOne SE PCI slot to IRQ routing
148  *
149  * repository: https://source.denx.de/u-boot/custodians/u-boot-avr32.git
150  * refspec: v2010.06
151  * file: board/MAI/AmigaOneG3SE/articiaS_pci.c
152  */
153 static int amigaone_pcihost_bus0_map_irq(PCIDevice *pdev, int pin)
154 {
155     int devfn_slot = PCI_SLOT(pdev->devfn);
156 
157     switch (devfn_slot) {
158     case 6:  /* On board ethernet */
159         return 3;
160     case 7:  /* South bridge */
161         return pin;
162     default: /* PCI Slot 1 Devfn slot 8, Slot 2 Devfn 9, Slot 3 Devfn 10 */
163         return pci_swizzle(devfn_slot, pin);
164     }
165 
166 }
167 
168 static void articia_realize(DeviceState *dev, Error **errp)
169 {
170     ArticiaState *s = ARTICIA(dev);
171     PCIHostState *h = PCI_HOST_BRIDGE(dev);
172     PCIDevice *pdev;
173 
174     bitbang_i2c_init(&s->smbus, i2c_init_bus(dev, "smbus"));
175     memory_region_init_io(&s->gpio_reg, OBJECT(s), &articia_gpio_ops, s,
176                           TYPE_ARTICIA, 4);
177 
178     memory_region_init(&s->mem, OBJECT(dev), "pci-mem", UINT64_MAX);
179     memory_region_init(&s->io, OBJECT(dev), "pci-io", 0xc00000);
180     memory_region_init_io(&s->reg, OBJECT(s), &articia_reg_ops, s,
181                           TYPE_ARTICIA, 0x1000000);
182     memory_region_add_subregion_overlap(&s->reg, 0, &s->io, 1);
183 
184     /* devfn_min is 8 that matches first PCI slot in AmigaOne */
185     h->bus = pci_register_root_bus(dev, NULL, articia_pcihost_set_irq,
186                                    amigaone_pcihost_bus0_map_irq, dev, &s->mem,
187                                    &s->io, PCI_DEVFN(8, 0), 4, TYPE_PCI_BUS);
188     pdev = pci_create_simple_multifunction(h->bus, PCI_DEVFN(0, 0),
189                                            TYPE_ARTICIA_PCI_HOST);
190     ARTICIA_PCI_HOST(pdev)->as = s;
191     pci_create_simple(h->bus, PCI_DEVFN(0, 1), TYPE_ARTICIA_PCI_BRIDGE);
192 
193     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->reg);
194     sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->mem);
195     qdev_init_gpio_out(dev, s->irq, ARRAY_SIZE(s->irq));
196 }
197 
198 static void articia_class_init(ObjectClass *klass, void *data)
199 {
200     DeviceClass *dc = DEVICE_CLASS(klass);
201 
202     dc->realize = articia_realize;
203     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
204 }
205 
206 /* TYPE_ARTICIA_PCI_HOST */
207 
208 static void articia_pci_host_cfg_write(PCIDevice *d, uint32_t addr,
209                                        uint32_t val, int len)
210 {
211     ArticiaState *s = ARTICIA_PCI_HOST(d)->as;
212 
213     pci_default_write_config(d, addr, val, len);
214     switch (addr) {
215     case 0x40:
216         s->gpio_base = val;
217         break;
218     case 0x44:
219         if (val != 0x11) {
220             /* FIXME what do the bits actually mean? */
221             break;
222         }
223         if (memory_region_is_mapped(&s->gpio_reg)) {
224             memory_region_del_subregion(&s->io, &s->gpio_reg);
225         }
226         memory_region_add_subregion(&s->io, s->gpio_base + 0x38, &s->gpio_reg);
227         break;
228     }
229 }
230 
231 static void articia_pci_host_class_init(ObjectClass *klass, void *data)
232 {
233     DeviceClass *dc = DEVICE_CLASS(klass);
234     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
235 
236     k->config_write = articia_pci_host_cfg_write;
237     k->vendor_id = 0x10cc;
238     k->device_id = 0x0660;
239     k->class_id = PCI_CLASS_BRIDGE_HOST;
240     /*
241      * PCI-facing part of the host bridge,
242      * not usable without the host-facing part
243      */
244     dc->user_creatable = false;
245 }
246 
247 /* TYPE_ARTICIA_PCI_BRIDGE */
248 
249 static void articia_pci_bridge_class_init(ObjectClass *klass, void *data)
250 {
251     DeviceClass *dc = DEVICE_CLASS(klass);
252     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
253 
254     k->vendor_id = 0x10cc;
255     k->device_id = 0x0661;
256     k->class_id = PCI_CLASS_BRIDGE_HOST;
257     /*
258      * PCI-facing part of the host bridge,
259      * not usable without the host-facing part
260      */
261     dc->user_creatable = false;
262 }
263 
264 static const TypeInfo articia_types[] = {
265     {
266         .name          = TYPE_ARTICIA,
267         .parent        = TYPE_PCI_HOST_BRIDGE,
268         .instance_size = sizeof(ArticiaState),
269         .class_init    = articia_class_init,
270     },
271     {
272         .name          = TYPE_ARTICIA_PCI_HOST,
273         .parent        = TYPE_PCI_DEVICE,
274         .instance_size = sizeof(ArticiaHostState),
275         .class_init    = articia_pci_host_class_init,
276         .interfaces = (InterfaceInfo[]) {
277               { INTERFACE_CONVENTIONAL_PCI_DEVICE },
278               { },
279         },
280     },
281     {
282         .name          = TYPE_ARTICIA_PCI_BRIDGE,
283         .parent        = TYPE_PCI_DEVICE,
284         .instance_size = sizeof(PCIDevice),
285         .class_init    = articia_pci_bridge_class_init,
286         .interfaces = (InterfaceInfo[]) {
287               { INTERFACE_CONVENTIONAL_PCI_DEVICE },
288               { },
289         },
290     },
291 };
292 
293 DEFINE_TYPES(articia_types)
294